Method of making tools having a core die and a cavity die

Abstract

The present invention relates to a method of making a molding tool comprising a core die and a cavity die. The method comprises (a) providing a first metal deposit comprising one of the cavity die or the core die, the first metal deposit having a die face, (b) providing a spray forming pattern on a portion of the die face of the first metal deposit,(c) spraying metal particles onto the first metal deposit and the spray forming pattern to form a second metal deposit comprising the other of the cavity die or the core die, and (d) removing the spray forming pattern from the first and second metal deposits.

What is claimed is:  
     
       1. A method of making a molding tool comprising a core die and a cavity die, said method comprising: 
       (a) providing a first steel deposit comprising one of the cavity die or the core die, the first deposit having a die face;  
       (b) forming a spray forming pattern, having a first shape, directly on a portion of the die face of the first deposit;  
       (c) spraying steel particles onto the first deposit and the spray forming pattern to form a second steel deposit comprising the other of the cavity die or the core die; and  
       (d) removing the spray forming pattern from the first and second steel deposits.  
     
     
       2. The method of claim  1 , further comprising separating the first deposit from the second deposit. 
     
     
       3. The method of claim  2  wherein the first deposit is separated from the second deposit prior to said step (d) removing the spray forming pattern from the deposits. 
     
     
       4. The method of claim  2  wherein the first deposit is separated from the second deposit after said step (d) removing said spray forming pattern from the deposits. 
     
     
       5. The method of claim  1  wherein the spray forming pattern is made of a metallic material. 
     
     
       6. The method of claim  1  wherein the spray forming pattern is made of a ceramic material. 
     
     
       7. The method of claim  5  wherein said step (d) of removing the spray forming pattern comprises heating the deposits and the pattern to a first temperature which is sufficient to melt the spray forming pattern but is not sufficient to melt the deposits. 
     
     
       8. The method of claim  7  wherein the spray forming pattern material comprises an alloy of tin and bismuth and the first temperature is between about 200° C. and about 500° C. 
     
     
       9. The method of claim  1  wherein the die face of the first metal deposit is coated with a release agent prior to said step (c). 
     
     
       10. The method of claim  9  wherein the release agent comprises boron nitride. 
     
     
       11. The method of claim  1  wherein the die face is mechanically prepped with a bead blaster prior to said step (c). 
     
     
       12. The method of claim  1  wherein said step (b) of forming the spray forming pattern directly on the first deposit comprises providing a casting mold directly on the first deposit, the casting mold having a first cavity having a second shape which is substantially similar to the first shape of the spray forming pattern, pouring liquified spray forming pattern material into the first cavity of the casting mold, and solidifying the liquified spray forming pattern material to form the spray forming pattern directly on the first deposit. 
     
     
       13. The method of claim  12  wherein the forming of the casting mold directly on the first deposit comprises placing the first deposit in an open box, placing a master on the first deposit, the master having a third shape which is substantially similar to the first shape, pouring liquified casting mold material into the box to cover at least the master and a portion of the first deposit, and solidifying the liquified casting mold material to form the casting mold. 
     
     
       14. The method of claim  13  further comprising removing the master from the box after the formation of the casting mold and prior to the pouring of the liquified spray forming pattern material into the cavity of the casting mold. 
     
     
       15. The method of claim  14  wherein at least a pour channel and a vent are formed in the casting mold after the liquified casting mold material is solidified to form the casting mold and prior to pouring the liquified spray forming pattern material into the cavity of the casting mold. 
     
     
       16. The method of claim  15  wherein the casting mold material comprises silicone. 
     
     
       17. The method of claim  12  wherein the casting mold is removed from the first deposit prior to the spraying in step (c). 
     
     
       18. The method of claim  12  wherein the first and second steel deposits are made from carbon steel material having a carbon content in the range of 0.01 to 0.9% by weight. 
     
     
       19. A method of making a molding tool comprising a core die, a cavity die and a first cavity having a first shape, said method comprising: 
       (a) providing a first deposit comprising one of the cavity die or the core die, the first deposit having a die face;  
       (b) forming a casting mold directly on the die face of the first deposit, the casting mold having a second cavity, the second cavity having a second shape which is substantially the same as the first shape;  
       (c) pouring liquified spray forming pattern material into the second cavity of the casting mold and solidifying the liquified spray forming pattern material to form a spray forming pattern directly on the first deposit, the spray forming pattern having a third shape which is substantially the same as the, first shape, the spray forming pattern material being selected from the group consisting of metal and ceramic;  
       (d) removing the casting mold from the first die;  
       (e) spraying carbon steel particles, originating from a sprayable carbon steel material in which the carbon content is in the range of 0.01 to 0.9% by weight, onto the first deposit and the spray forming pattern to form a second deposit made of carbon steel, the second deposit comprising the other of the cavity die or the core die; and  
       (f) removing the spray forming pattern from the first and second steel deposits.  
     
     
       20. The method of claim  19  wherein the forming of the casting mold directly on the first deposit comprises placing the first deposit in an open box, placing a master on the first deposit, the master having a fourth shape which is substantially similar to the first shape, pouring liquified casting mold material into the box to cover at least the master and a portion of the first deposit, solidifying the liquified casting mold material to form the casting mold, and removing the master from the box after the formation of the casting mold and prior to the pouring of the liquified spray forming pattern material into the cavity of the casting mold.